/**模拟事件*/
function FireEvent(elem, eventName)
	{
		if (document.all)
		{
			elem.fireEvent(eventName);
		}
		else
		{
			 var evt = document.createEvent('HTMLEvents');
			 eventName = eventName.substring(2);
			 evt.initEvent(eventName,true,true);
			 elem.dispatchEvent(evt);
		}
	}